Decayed animals and human skeletons

What’s in common between decayed animals and the human skeletons?
You are not allowed to play around with such things in India. And, apparently, there were a lot of folks over there who were willing to do such a morbid things. You can easily picture them: dirty looking skinny guys with the grey beard and long fingernails (and toenails, also) sitting on a rotten corpse of bengali tiger and polishing the bones of their grandma’s skeleton.